Recent Advances in Nanoarchitectonics of SnO2 Clusters and Their Applications in Catalysis.

Tin dioxide nanoclusters are very effective as catalysts for various reactions including CO2 conversion and Friedel-Crafts acylation for pharmaceuticals. The nanoarchitectonics of SnO2 could be controlled by different synthetic strategies. In the current article, we have presented synthesis of SnO2 nanoclusters and their applications in catalysis. We have also reviewed computational studies on SnO2 nanoclusters for using them in nanoarchitectonics and catalytic conversion of CO2 to useful chemicals. Optimized structures of various cluster sizes are presented. The present and future perspectives of SnO2 catalysts in biomass conversions are also given.

Preferential Sites for Adsorption of CO on Au6 Clusters Using Density Functional Theory Based Reactivity Descriptors.

Nanoarchitectonics of neutral Au6 cluster upon addition and removal of one electron have been studied using density functional based reactivity descriptors. We studied the response of various sites of cationic, neutral and anionic Au6 clusters towards impending electrophilic and nucleophilic attacks using DFT based local reactivity descriptors, viz, Fukui function for nucleophilic attack f+. Fukui function for electrophilic attack f-, relative nucleophilicity f+/f- and relative electrophilicity f+/f-. Based on these parameters different types of unique atoms have been identified for each cluster. Reactivity predictions for the unique atoms of the minimum energy planar triangular Au6 structure have been verified by using CO as a probe molecule. It has been found adsorption of CO molecules on gold cluster brings about structural changes in the cluster and that the CO molecule prefers the apex site for adsorption onto the triangular Au6 cluster as compared to the mid site.